The subject matter described herein relates generally to a thermal interface material, and, more particularly, a thermal interface material for reducing thermal resistance between a circuit card assembly (CCA) and a chassis.
Enclosures designed to remove heat from a CCA by way of thermal conduction, such as those assemblies containing high power devices, are increasingly challenged to remove higher levels of heat. This is because newly developed processing devices typically contain more circuitry and therefore tend to generate higher heat loads, or because components are smaller, thus permitting a CCA to contain more components, thereby increasing an amount of heat generated per CCA.
Various systems have been devised for pressing, via a board retainer, opposite edges of the thermal interface of a CCA to a chassis which acts as a heat sink to carry away heat generated by CCA components on opposite sides of the thermal interface. However, currently, a thermal interface between a CCA and a chassis is metal to metal without a thermal intermediate material between the two metals. The metal to metal interface is poor thermally, with a typical difference in temperature (ΔT) in the order of 10° C. from the thermal interface of a CCA to a cold wall of a chassis. While a metal to metal interface may be sufficient where CCA wattage is low, new designs of CCAs are dissipating progressively more heat as electronic devices become smaller and/or operate at higher speeds, rendering the metal to metal interface inadequate. As such, heat transferability breaks down or is insufficient, and performance of an electronic device in which they are used is adversely affected.